Various vehicular clutch systems of the hydraulic type have been suggested heretofore. In general, these systems include a pedal-operated rotatable cross shaft which has a small actuating rod attached thereto operative to control a clutch master cylinder, the output fluid of which in turn controls a slave cylinder which has a piston rod that engages a throw-out fork which operates to release the vehicle clutch. Such systems present a continuing maintenance problem, particularly in conjunction with vehicles such as delivery trucks which are subject to numerous start and stop operations. More particularly, after the vehicle has been operated for a period of time, the hydraulic system tends to develop leaks (or, in some cases, there may even be a rupture of a fluid line in the system), air bleeds into the system, and the system fails to operate properly to depress the throw-out fork thereby preventing release of the clutch and shifting of the vehicle gears. While these problems are correctable by appropriate repair procedures, and can be minimized by periodic maintenance procedures which include the replacement of deteriorating parts of the actuator system, such repair and maintenance procedures are time consuming and costly.
The present invention solves these problems through the provision of a mechanical linkage device, provided in kit form and installable as a unit at the time of a repair or maintenance operation, in replacement of the pre-existing hydraulic actuator in the vehicular clutch system to convert the pre-existing hydraulic clutch system into one which operates mechanically. The conversion linkage, when installed, eliminates all future repair and maintenance problems arising by reason of hydraulic system leaks or failures, and assures that depression of the clutch pedal in the vehicle and consequent rotation of the cross shaft depresses the throw-out fork to release the clutch reliably under extended and heavy service conditions.